Memory cards are integrated circuit (IC) cards including non-volatile memory and a controller, which controls the operation of the memory card. Such memory cards can be temporarily connected to host devices, such as, for example, personal computers (PCs), cellular telephones, personal digital assistants (PDAs), digital cameras, portable audio players and other host electronic devices for storage of data. A plurality of standards exists that specify different types of memory cards, such as, for example, SD (Secure Digital) cards, CF (Compact Flash) cards and MMCs (Multimedia Cards). A further example of a memory card, in the sense the term is used herein, is a USB (Universal Serial Bus) flash memory stick.
Memory cards of the type described before may provide a security mechanism for protecting data from unauthorized access. This allows for storing sensitive data in the memory card, such as, for example, banking details of the card owner, medical data of the card owner and personal photographs or other personal data.
The card owner may access the data using a credential, such as, for example, a password. However, the user may wish to make the protected data accessible for certain persons in some situations. For instance, the card owner may wish to allow his doctor to read protected medical data stored in the memory card or to make personal photos available to a friend.